Piston



J. -A. COLE AND L. 'J. SHORTER.

Patented July 25, 1922.

NVENTORS ATTORNEY 5 UNITED STATES PATENT OFFICE.

JOHN ALBERT COLE AND LEO JOSEPI-I SHORTER, OF COVENTRY, ENGLAN'D. I

PISTON.

Specification of Letters Patent. Patented July 25, 1922,

Application filed November 14, 1921. Serial No. 515,057.

T 0 all "(chm/tit ,vzay concern:

Be it known that we, JOH ALBERT Come and LEO Josnrrr SHORTER, both subjects oi the King of England, residing at Coventry, in the county of lVarwick, England, have invented certain new and useful Improvements in Pistons, of which the following is a specification.

With internal combustion engines used 011 motor vehicles, it is very desirable that the piston should remain always in contact with one side of the cylinder, as otherwise noise and slap occur as the contact ,of the piston changes from one wall of the cylinder to the other, when the connecting rod passes beyond the dead centre.

Many suggestions have been made toensure this permanent contact with one wall of the cylinder. In most cases the pistons are slit or provided with springs, and it is the object of the present invention to provide a simple means, applicable if necessary to existing pistons, whereby contact can always be maintained with the same wall of the cylinder. 7

According to this invention, the crown of the piston is flat and slopes from one side to the other so as to be out of perpendicular to the wall of the cylinder, that is, its plane is oblique to the axis of the cylinder. Thus, when pressure occurs upon the top of the crown of the piston there is a small lateral component of thrust forcing it towards the desired cylinder wall, and this lateral thrust prevents the piston leaving that wall as the connecting rodpasses the dead centre.

The accompanying sectional drawing 7 shows a piston A with the top B of the crown sloping at a slight angle from right to left so that the piston always keeps in con tact with the cylinder wall C.

In an internal combustion engine having a light weight piston of 80 millimetres bore, we have found that the desired'result is ob tained ifone side of the piston is from two to five millimetres higher than the other side. lVe-do not, however, wish to limit the invention to these dimensions. e have also found that good results can be obtained by maintaining the thrust either on the wall with which the piston normally is in contact during the compression stroke; or on that with With this arrangement, apart from obviat ing noise or slap, greater efliciency' can be obtained because the resultant force, due to the angularity of the crown of the piston can be caused to react during theexplosion stroke against the thrust imposed upon the cylinder wall due to the angularity of the connecting rod.

,lVe are aware that in two-stroke enginesthe crown of the piston hasbeen sloped in such manner as to form a baflie thereon, but the object of this has been to attain ascavenging effect and not, so far as we are aware, to produce a side thrust upon the wall or" the cylinder, which is the object of our invention.

By this invention a very simple means is provided for maintaining permanent conwould be rendered worse than before, during rotation in the opposite direction.

What we claim as our invention, and dc sue to secure by Letters Patent of the United States is I p A piston 'for an internal combustion engine in which the whole of the crown of the piston is flat and the plane thereof is oblique to the axis of the cylinder, the piston having a wrist pin bearing cutting the piston axis; the direction of slope of the crown being such that theedge thereofnearest the mouth of the cylinder is against that side of the cylinder which takes the whole side thrust during the entire working stroke.

In testimony whereof we have signed our names to this specification in the presence of two SllbSCIlblIlg WltIlQSSGS JOHN ALBERT COLE. Leo JOSEPH SHORTER.

lVitnesses:

JAs. T. AUBUTT, i W. GAMPBELLHARGRAVES. 

